Long-term health and economic benefits of switching to tenofovir alafenamide versus continuing on entecavir in chronic hepatitis B patients with low-level viremia in Saudi Arabia.

BACKGROUND: Despite the success of current treatments, many chronic hepatitis B (CHB) patients still live with low-level viremia [LLV] resulting in liver disease progression. This study evaluated the long-term health and economic impact of switching to tenofovir alafenamide (TAF) from entecavir (ETV) in Saudi Arabia (SA) in chronic hepatitis B (CHB) LLV patients. METHODS: A hybrid decision tree Markov state-transition model was developed to simulate a cohort of patients with CHB LLV treated with ETV and switched to TAF over a lifetime horizon in SA. While on treatment, patients either achieved complete virologic response (CVR) or maintained LLV. CVR patients experienced slower progression to advanced liver disease stages as compared to LLV patients. Demographic data, transition probabilities, treatment efficacy, health state costs, and utilities were sourced from published literature. Treatment costs were sourced from publicly available databases. RESULTS: Base case analysis found that over a lifetime horizon, switching to TAF versus remaining on ETV increased the proportion of patients achieving CVR (76% versus 14%, respectively). Switching to TAF versus remaining on ETV resulted in a reduction in cases of compensated cirrhosis (-52%), decompensated cirrhosis (-5%), hepatocellular carcinoma (-22%), liver transplants (-12%), and a 37% reduction in liver-related deaths. Switching to TAF was cost-effective with an incremental cost-effectiveness ratio of $57,222, assuming a willingness-to-pay threshold of three times gross national income per capita [$65,790/QALY]. CONCLUSIONS: This model found that switching to TAF versus remaining on ETV in SA CHB LLV patients substantially reduced long-term CHB-related morbidity and mortality and was a cost-effective treatment strategy.

Hepatitis C donor positive to recipient negative solid organ transplants: Early direct acting antiviral insurance approval rates with and without documented viremia.

BACKGROUND: Current guidelines support early initiation of direct-acting antivirals (DAA) in hepatitis C virus (HCV) donor positive and recipient negative (D+/R-) solid organ transplants (SOTs). According to experts, access to DAA therapy is a key barrier to early treatment. METHODS: This single-center, retrospective study assessed the rate of DAA prescription approval with or without confirmed HCV viremia, time to approval, and reasons for denial in HCV D+/R- SOTs. RESULTS: All 51 patients received insurance approval for DAA therapy following transplantation regardless of confirmed HCV viremia at time of prior authorization (PA) submission. Same day PA approval was obtained in 51% of cases. Appeals received approval within a median of 2 days from submission. CONCLUSION: Our findings suggest confirmed HCV viremia may not be as significant of a barrier to DAA access and may encourage other health systems to consider early initiation of DAA therapy in their HCV D+/R- transplants.

Current management of CMV infection in cancer patients (solid tumors). Epidemiology and therapeutic strategies.

Little evidence is available regarding the incidence of CMV disease in patients with solid cancers. Latest data show that approximately 50 % of these patients with CMV PCR positivity developed clinically relevant CMV-viremia, and would require specific therapy. In the clinical arena, CMV reactivation is an important differential diagnosis in the infectological work up of these patients, but guidelines of management on this subject are not yet available. CMV reactivation should be considered during differential diagnosis for patients with a severe decline in lymphocyte counts when receiving chemoradiotherapy or immunochemotherapy with lymphocyte-depleting or blocking agents. Monitoring of CMV reactivation followed by the implementation of preemptive strategies or the establishment of early antiviral treatment improves the prognosis and reduces the morbidity and mortality of these patients.

A public health approach to monitoring HIV with resistance to HIV pre-exposure prophylaxis.

BACKGROUND: The risk of HIV pre-exposure prophylaxis (PrEP) failure with sufficient medication adherence is extremely low but has occurred due to transmission of a viral strain with mutations conferring resistance to PrEP components tenofovir (TDF) and emtricitabine (FTC). The extent to which such strains are circulating in the population is unknown. METHODS: We used HIV surveillance data to describe primary and overall TDF/FTC resistance and concurrent viremia among people living with HIV (PLWH). HIV genotypes conducted for clinical purposes are reported as part of HIV surveillance. We examined the prevalence of HIV strains with mutations conferring intermediate to high level resistance to TDF/FTC, defining primary resistance (predominantly K65R and M184I/V mutations) among sequences reported within 3 months of HIV diagnosis and total resistance for sequences reported at any time. We examined trends in primary resistance during 2010-2019 and total resistance among all PLWH in 2019. We also monitored resistance with viremia (≥1,000 copies/mL) at the end of 2019 among PLWH. RESULTS: Between 2010 and 2019, 2,172 King County residents were diagnosed with HIV; 1,557 (72%) had a genotypic resistance test within three months; three (0.2%) had primary TDF/FTC resistance with both K65R and M184I/V mutations. Adding isolated resistance for each drug resulted in 0.3% with primary TDF resistance and 0.8% with primary FTC resistance. Of 7,056 PLWH in 2019, 4,032 (57%) had genotype results, 241 (6%) had TDF/FTC resistance and 15 (0.4% of those with a genotype result) had viremia and TDF/FTC resistance. CONCLUSIONS: Primary resistance and viremia combined with TDF/FTC resistance are uncommon in King County. Monitoring trends in TDF/FTC resistance coupled with interventions to help ensure PLWH achieve and maintain viral suppression may help ensure that PrEP failure remains rare.

Incidence, risk factors, outcomes, and clinical management of BK viremia in the modern era of kidney transplantation.

BK viremia is endemic among kidney transplant recipients (KTRs). Incidence, risk factors, outcomes, and clinical management of detectable versus high BK viremia have not been considered previously in KTR in the modern era. This observational study examined KTR transplanted between January 1, 2009 and December 31, 2016. Any BK viral load in the serum constituted detectable BK viremia and ≥103 copies/ml constituted high viremia. Among 1193 KTRs, the cumulative probability of developing detectable and high BK viremia within 2 years posttransplant were 27.8% and 19.6%, respectively. Significant risk factors for detectable BK viremia included recipient age (HR 1.02 [95% CI: 1.01, 1.03]) and donor age (HR 1.01 [95% CI: 1.00, 1.02]). Recipient age also predicted high BK viremia (HR 1.02 [95% CI: 1.01, 1.03]), whereas White race (HR 0.70 [95% CI: 0.52, 0.95]), nondepleting induction therapy (HR 0.61 [95% CI: 0.42, 0.89]), and delayed graft function (HR 0.61 [95% CI: 0.42, 0.88]) were protective. Mean estimated glomerular filtration rates were 4.28 ml/min/1.72 m2 (95% CI: 2.71, 5.84) lower with detectable BK viremia. Although low viral load was usually not acted upon at first presentation, antiproliferative dose reductions were the most common initial management. BK viremia remains a common early complication in a modern cohort of KTRs. These findings highlight the benefit of early BKV monitoring in addition to intensive clinical management. Clinical responses beyond first positive BK viremia tests, and their implications for graft outcomes, merit further investigation.

Cost-effectiveness and system-wide impact of using Hepatitis C-viremic donors for heart transplant.

BACKGROUND: The advent of direct-acting antiviral therapy for Hepatitis C (HCV) has made using HCV-viremic donors a viable strategy to address the donor shortage in heart transplantation. We employed a large-scale simulation to evaluate the impact and cost-effectiveness of using HCV-viremic donors for heart transplant. METHODS: We simulated detailed histories from time of listing until death for the real-world cohort of all adults listed for heart transplant in the United States from July 2014 to June 2019 (n = 19,346). This population was imputed using historical data and captures "real-world" heterogeneity in geographic and clinical characteristics. We estimated the impact of an intervention in which all candidates accept HCV+ potential donors (n = 472) on transplant volume, waitlist outcomes, and lifetime costs and quality-adjusted life years (QALYs). RESULTS: The intervention produced 232 more transplants, 132 fewer delistings due to deterioration, and 50 fewer waitlist deaths within this 5-year cohort and reduced wait times by 3% to 11% (varying by priority status). The intervention was cost-effective, adding an average of 0.08 QALYs per patient at a cost of $124 million ($81,892 per QALY). DAA therapy and HCV care combined account for 11% this cost, with the remainder due to higher costs of transplant procedures and routine post-transplant care. The impact on transplant volume varied by blood type and region and was correlated with donor-to-candidate ratio (ρ = 0.71). CONCLUSIONS: Transplanting HCV+ donor hearts is likely to be cost-effective and improve waitlist outcomes, particularly in regions and subgroups experiencing high donor scarcity.

Risk Assessment of Progressive Multifocal Leukoencephalopathy in Multiple Sclerosis Patients during 1 Year of Ocrelizumab Treatment.

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) caused by the JC virus is the main limitation to the use of disease modifying therapies for treatment of multiple sclerosis (MS). METHODS: To assess the PML risk in course of ocrelizumab, urine and blood samples were collected from 42 MS patients at baseline (T0), at 6 (T2) and 12 months (T4) from the beginning of therapy. After JCPyV-DNA extraction, a quantitative-PCR (Q-PCR) was performed. Moreover, assessment of JCV-serostatus was obtained and arrangements' analysis of non-coding control region (NCCR) and of viral capsid protein 1 (VP1) was carried out. RESULTS: Q-PCR revealed JCPyV-DNA in urine at all selected time points, while JCPyV-DNA was detected in plasma at T4. From T0 to T4, JC viral load in urine was detected, increased in two logarithms and, significantly higher, compared to viremia. NCCR from urine was archetypal. Plasmatic NCCR displayed deletion, duplication, and point mutations. VP1 showed the S269F substitution involving the receptor-binding region. Anti-JCV index and IgM titer were found to statistically decrease during ocrelizumab treatment. CONCLUSIONS: Ocrelizumab in JCPyV-DNA positive patients is safe and did not determine PML cases. Combined monitoring of ocrelizumab's effects on JCPyV pathogenicity and on host immunity might offer a complete insight towards predicting PML risk.

Cost-effectiveness of using hepatitis C viremic hearts for transplantation into HCV-negative recipients.

Outcomes following hepatitis C virus (HCV)-viremic heart transplantation into HCV-negative recipients with HCV treatment are good. We assessed cost-effectiveness between cohorts of transplant recipients willing and unwilling to receive HCV-viremic hearts. Markov model simulated long-term outcomes among HCV-negative patients on the transplant waitlist. We compared costs (2018 USD) and health outcomes (quality-adjusted life-years, QALYs) between cohorts willing to accept any heart and those willing to accept only HCV-negative hearts. We assumed 4.9% HCV-viremic donor prevalence. Patients receiving HCV-viremic hearts were treated, assuming $39 600/treatment with 95% cure. Incremental cost-effectiveness ratios (ICERs) were compared to a $100 000/QALY gained willingness-to-pay threshold. Sensitivity analyses included stratification by blood type or region and potential negative consequences of receipt of HCV-viremic hearts. Compared to accepting only HCV-negative hearts, accepting any heart gained 0.14 life-years and 0.11 QALYs, while increasing costs by $9418/patient. Accepting any heart was cost effective (ICER $85 602/QALY gained). Results were robust to all transplant regions and blood types, except type AB. Accepting any heart remained cost effective provided posttransplant mortality and costs among those receiving HCV-viremic hearts were not >7% higher compared to HCV-negative hearts. Willingness to accept HCV-viremic hearts for transplantation into HCV-negative recipients is cost effective and improves clinical outcomes.

Genotype-Informed Versus Empiric Management Of VirEmia (GIVE MOVE): study protocol of an open-label randomised clinical trial in children and adolescents living with HIV in Lesotho and Tanzania.

BACKGROUND: Globally, the majority of people living with HIV have no or only limited access to HIV drug resistance testing to guide the selection of antiretroviral drugs. This is of particular concern for children and adolescents, who experience high rates of treatment failure. The GIVE MOVE trial assesses the clinical impact and cost-effectiveness of routinely providing genotypic resistance testing (GRT) to children and adolescents living with HIV who have an unsuppressed viral load (VL) while taking antiretroviral therapy (ART). METHODS: GIVE MOVE is an open-label randomised clinical trial enrolling children and adolescents (≥6 months to <19 years) living with HIV with a VL ≥400 copies/mL (c/mL) while taking first-line ART. Recruitment takes place at sites in Lesotho and Tanzania. Participants are randomised in a 1:1 allocation to a control arm receiving the standard of care (3 sessions of enhanced adherence counselling, a follow-up VL test, continuation of the same regimen upon viral resuppression or empiric selection of a new regimen upon sustained elevated viremia) and an intervention arm (GRT to inform onward treatment). The composite primary endpoint is the occurrence of any one or more of the following events during the 36 weeks of follow-up period: i) death due to any cause; ii) HIV- or ART-related hospital admission of ≥24 h duration; iii) new clinical World Health Organisation stage 4 event (excluding lymph node tuberculosis, stunting, oral or genital herpes simplex infection and oesophageal candidiasis); and iv) no documented VL <50 c/mL at 36 weeks follow-up. Secondary and exploratory endpoints assess additional health-related outcomes, and a nested study will assess the cost-effectiveness of the intervention. Enrolment of a total of 276 participants is planned, with an interim analysis scheduled after the first 138 participants have completed follow-up. DISCUSSION: This randomised clinical trial will assess if the availability of resistance testing improves clinical outcomes in children and adolescents with elevated viremia while taking ART. TRIAL REGISTRATION: This trial is registered with ClinicalTrials.gov ( NCT04233242 ; registered 18.01.2020). More information: www.givemove.org .

Cost analysis of ganciclovir and foscarnet in recipients of allogeneic hematopoietic cell transplant with cytomegalovirus viremia.

BACKGROUND: Ganciclovir (GCV) and foscarnet (FOS) are the most commonly used antivirals for preemptive treatment of cytomegalovirus (CMV) viremia in recipients of allogeneic hematopoietic cell transplantation (alloHCT). The current literature indicates similar efficacy between these agents. Thus, the primary consideration for choice of initial anti-CMV treatment is the safety profile, time period after alloHCT, and concern of myelosuppression or renal dysfunction. METHODS: Herein, we retrospectively reviewed medical records of 124 alloHCT recipients who received GCV or FOS between April 27, 2014, and December 31, 2015, during the first year post-transplant. Healthcare resource use included drug, hospitalization, home health, dialysis, and growth factor costs. RESULTS: Total duration of therapy was longer in the GCV group (37 days vs 28 days, P = .21) but hospitalization days were similar (9 days) in both groups. The total treatment cost was significantly lower in the GCV group ($38 100 vs $59 400, P < .05). CONCLUSION: Preemptive anti-CMV therapy is associated with major healthcare resource costs, which were greater in patients who required FOS than those who were treated with GCV.

Temporal Changes and Regional Variation in Acceptance of Hepatitis C Virus-Viremic Livers.

The high efficacy of current hepatitis C virus (HCV) therapy and increased numbers of HCV-infected deceased donors have changed the paradigm of HCV in liver transplantation (LT). Modeling studies have been performed to evaluate the optimal timing of HCV treatment (before versus after LT) in HCV-infected patients and to assess the cost-effectiveness of transplanting HCV-infected livers into HCV- patients. However, these models rely on historical data and have not quantified the temporal changes in the median Model for End-Stage Liver Disease (MELD) score at transplant of recipients of an HCV-infected liver across geographic areas. We performed a retrospective cohort study of Organ Procurement and Transplantation Network/United Network for Organ Sharing (UNOS) data of nonstatus 1 deceased donor LT recipients from January 1, 2016, to December 31, 2018, and we calculated the difference in allocation MELD score in recipients of HCV nucleic acid test (NAT)- versus NAT+ livers by year and UNOS region. We used Pearson correlation coefficients to assess the relationship between MELD score difference in recipients of HCV NAT+ versus HCV NAT- livers and the proportion of non-HCV recipients of HCV NAT+ livers. Nationally, the allocation MELD score difference at LT in recipients of HCV NAT+ versus NAT- livers did not change (4-point difference). This stability was seen in regions 3, 5, and 10. In regions 1, 7, 8, 9, and 11, the MELD score difference decreased, which is a diminishing advantage. However, in regions 2 and 4, it increased, which is a rising advantage. In 2018, recipients of HCV NAT+ livers had a lower MELD score in 9/11 regions, and the MELD score advantage of accepting HCV NAT+ livers had a moderate inverse correlation with the regional use in non-HCV patients (r = -0.53). These data should be used to inform clinicians of the pre- and post-LT trade-offs of HCV treatment.

The impact of direct-acting anti-virals on the hepatitis C care cascade: identifying progress and gaps towards hepatitis C elimination in the United States.

BACKGROUND: The hepatitis C virus (HCV) care cascade has changed dramatically following the introduction of direct-acting anti-virals (DAAs). Up-to-date estimates of the cascade are needed to monitor progress, identify key gaps and inform policy. AIM: To estimate the current and future HCV care cascade in the United States, nationally and in select subpopulations of interest. METHODS: We used a previously validated mathematical model to simulate the landscape of HCV in the United States from 2011 onwards, accounting for HCV screening policy updates, newer HCV treatments and rising HCV incidence. RESULTS: By the end of 2018, of 4.29 million HCV persons alive, 2.71 million (63%) were actively viremic, 2.24 million (52%) aware and 1.58 million (37%) cured. By 2030, under the status quo, of 3.65 million HCV persons alive, 1.88 million (51%) would be viremic, 2.25 million (62%) aware and 1.77 million (49%) cured. The HCV care cascade in 2018 differed substantially by subpopulation: of 1.34 million incarcerated HCV persons, 96% were viremic, 36% aware and 4% cured; of 0.87 million HCV persons in Medicare, 31% were viremic, 72% aware and 69% cured; and of 0.37 million HCV persons in Medicaid, 49% were viremic, 54% aware and 51% cured. Implementing universal screening, providing unrestricted treatment and controlling HCV incidence were factors found to have the largest effect on improving the HCV care cascade. CONCLUSIONS: Since the launch of DAAs, the HCV care cascade has shifted towards higher awareness and treatment rates; however, additional interventions are needed to move towards HCV elimination.

Australia on track to achieve WHO HCV elimination targets following rapid initial DAA treatment uptake: A modelling study.

Subsidized direct-acting antiviral (DAA) treatment recently became available to all adults living with chronic hepatitis C virus (HCV) in Australia. Based on rapid uptake (32 600 people initiated DAA in 2016), we estimated the impact on HCV epidemiology and mortality in Australia and determined if Australia can meet the WHO HCV elimination targets by 2030. Using a mathematical model, we simulated pessimistic, intermediate and optimistic DAA treatment scenarios in Australia over 2016-2030. We assumed treatment and testing rates were initially higher for advanced fibrosis and the same across HCV transmission risk level sub-populations. We also assumed constant testing rates after 2016. We compared the results to the 2015 level and a counterfactual (IFN-based) scenario. During 2016-2030, we estimated an intermediate DAA treatment scenario (2016, 32 600 treated; 2017, 21 370 treated; 2018 17 100 treated; 2019 and beyond, 13 680 treated each year) would avert 40 420 new HCV infections, 13 260 liver-related deaths (15 320 in viraemic; -2060 in cured) and 10 730 HCC cases, equating to a 53%, 63% and 75% reduction, respectively, compared to the IFN-based scenario. The model also estimated that Australia will meet the WHO targets of incidence and treatment by 2028. Time to a 65% reduction in liver-related mortality varied considerably between HCV viraemic only cases (2026) and all cases (2047). Based on a feasible DAA treatment scenario incorporating declining uptake, Australia should meet key WHO HCV elimination targets in 10 to15 years. The pre-DAA escalation in those with advanced liver disease makes the achievement of the liver-related mortality target difficult.

Epidemiology and Immune Pathogenesis of Viral Sepsis.

Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. Sepsis can be caused by a broad range of pathogens; however, bacterial infections represent the majority of sepsis cases. Up to 42% of sepsis presentations are culture negative, suggesting a non-bacterial cause. Despite this, diagnosis of viral sepsis remains very rare. Almost any virus can cause sepsis in vulnerable patients (e.g., neonates, infants, and other immunosuppressed groups). The prevalence of viral sepsis is not known, nor is there enough information to make an accurate estimate. The initial standard of care for all cases of sepsis, even those that are subsequently proven to be culture negative, is the immediate use of broad-spectrum antibiotics. In the absence of definite diagnostic criteria for viral sepsis, or at least to exclude bacterial sepsis, this inevitably leads to unnecessary antimicrobial use, with associated consequences for antimicrobial resistance, effects on the host microbiome and excess healthcare costs. It is important to understand non-bacterial causes of sepsis so that inappropriate treatment can be minimised, and appropriate treatments can be developed to improve outcomes. In this review, we summarise what is known about viral sepsis, its most common causes, and how the immune responses to severe viral infections can contribute to sepsis. We also discuss strategies to improve our understanding of viral sepsis, and ways we can integrate this new information into effective treatment.

HCV core antigen as an alternative to HCV RNA testing in the era of direct-acting antivirals: retrospective screening and diagnostic cohort studies.

BACKGROUND: Direct-acting antivirals for chronic hepatitis C (HCV) infection have reduced the need for on-treatment HCV RNA monitoring. We assessed the accuracy and cost implications of using HCV core antigen testing to replace HCV RNA testing for confirmation of diagnosis, on-treatment monitoring, and determination of sustained virological response (SVR). METHODS: In a retrospective screening cohort study, de-identified residual serum from unselected samples were obtained from commercial laboratories in Ontario, Canada. Samples from each 5-year age-sex band from birth years 1945-74 collected from Aug 1, 2014, to Feb 28, 2015, were included. All samples that tested positive for HCV antibodies, and 10% of samples that tested negative for HCV antibodies, were tested for HCV core antigen and HCV RNA. A retrospective clinical cohort study was also done using blood samples from patients with confirmed HCV infection collected at four tertiary academic centres: one in Canada, two in Germany, and one in the USA. For assessment of SVR, we included samples from patients who started direct-acting antiviral-based treatment (excluding telaprevir and boceprevir) with or without peginterferon, ribavirin, or both, from Jan 1, 2014, to March 31, 2015. To ensure inclusion of adequate numbers for analysis, patients who relapsed after any treatment regimen were included. Serum samples included in the study were from baseline, week 4 on-treatment (only for patients treated with direct-acting antivirals), end of treatment, and week 12 or 24 of follow-up. The sensitivity and specificity of core antigen testing as a diagnostic tool was assessed in the screening cohort, using HCV RNA as a reference. The sensitivity and specificity of core antigen testing as well as its concordance with HCV RNA testing in the clinical cohort was assessed at baseline, week 4 on-treatment, and at weeks 12 or 24 after the end of treatment in patients undergoing therapy with direct-acting antivirals. The cost-effectiveness of core antigen testing with and without confirmatory HCV RNA testing for negative samples was also assessed. FINDINGS: From 10 006 samples in the screening cohort, 75 of 80 viraemic (HCV RNA-positive) samples tested positive for HCV core antigen (sensitivity 94%, 95% CI 86-98), and none of the 993 HCV RNA-negative samples tested positive for HCV core antigen (specificity 100%, 95% CI 94-100). The five viraemic samples that tested negative for HCV core antigen had low corresponding HCV RNA concentrations. In the clinical cohort, two (1%) of 202 baseline samples tested negative for HCV core antigen; one had a low HCV RNA concentration (468 IU/mL), the other had a high HCV RNA concentration (>2 000 000 IU/mL). By week 4 of treatment, HCV core antigen concentrations decreased in all patients but were not predictive of SVR. Although there was good concordance between HCV RNA and HCV core antigen results at 12 weeks after the end of treatment (r=0·97; p<0·0001), three of the 148 patients who achieved SVR at 12 weeks tested HCV core antigen positive. 12 weeks after the end of treatment, HCV core antigen was undetectable in one (1%) of 71 samples from patients who were identified as having relapsed according to HCV RNA detection. On-treatment and end-of-treatment testing of core antigen or HCV RNA provided little clinical value. The use of HCV core antigen testing as a confirmatory diagnostic strategy was cost saving relative to HCV RNA testing, with a reduction of CAD$0·29-3·70 per patient screened depending on whether HCV RNA testing was used to confirm HCV core antigen-negative results. INTERPRETATION: These data support the use of HCV core antigen testing to document HCV viraemia in a cost-saving diagnostic algorithm. In a treatment setting, HCV core antigen testing can be used instead of HCV RNA testing for diagnosis and documentation of treatment adherence, but it might not be adequate to determine SVR. This approach might improve access to care, particularly in low-income and middle-income countries. FUNDING: Abbott Diagnostics and Toronto Centre for Liver Disease.

Preclinical assessment of antiviral combination therapy in a genetically humanized mouse model for hepatitis delta virus infection.

Chronic delta hepatitis, caused by hepatitis delta virus (HDV), is the most severe form of viral hepatitis, affecting at least 20 million hepatitis B virus (HBV)-infected patients worldwide. HDV/HBV co- or superinfections are major drivers for hepatocarcinogenesis. Antiviral treatments exist only for HBV and can only suppress but not cure infection. Development of more effective therapies has been impeded by the scarcity of suitable small-animal models. We created a transgenic (tg) mouse model for HDV expressing the functional receptor for HBV and HDV, the human sodium taurocholate cotransporting peptide NTCP. Both HBV and HDV entered hepatocytes in these mice in a glycoprotein-dependent manner, but one or more postentry blocks prevented HBV replication. In contrast, HDV persistently infected hNTCP tg mice coexpressing the HBV envelope, consistent with HDV dependency on the HBV surface antigen (HBsAg) for packaging and spread. In immunocompromised mice lacking functional B, T, and natural killer cells, viremia lasted at least 80 days but resolved within 14 days in immunocompetent animals, demonstrating that lymphocytes are critical for controlling HDV infection. Although acute HDV infection did not cause overt liver damage in this model, cell-intrinsic and cellular innate immune responses were induced. We further demonstrated that single and dual treatment with myrcludex B and lonafarnib efficiently suppressed viremia but failed to cure HDV infection at the doses tested. This small-animal model with inheritable susceptibility to HDV opens opportunities for studying viral pathogenesis and immune responses and for testing novel HDV therapeutics.

Forecasting Hepatitis C liver disease burden on real-life data. Does the hidden iceberg matter to reach the elimination goals?

BACKGROUND & AIMS: Advances in direct-acting antiviral treatment of HCV have reinvigorated public health initiatives aimed at identifying affected individuals. We evaluated the possible impact of only diagnosed and linked-to-care individuals on overall HCV burden estimates and identified a possible strategy to achieve the WHO targets by 2030. METHODS: Using a modelling approach grounded in Italian real-life data of diagnosed and treated patients, different linkage-to-care scenarios were built to evaluate potential strategies in achieving the HCV elimination goals. RESULTS: Under the 40% linked-to-care scenario, viraemic burden would decline (60%); however, eligible patients to treat will be depleted by 2025. Increased case finding through a targeted screening strategy in 1948-1978 birth cohorts could supplement the pool of diagnosed patients by finding 75% of F0-F3 cases. Under the 60% linked-to-care scenario, viraemic infections would decline by 70% by 2030 but the patients eligible for treatment will run out by 2028. If treatment is to be maintained, a screening strategy focusing on 1958-1978 birth cohorts could capture 55% of F0-F3 individuals. Under the 80% linked-to-care scenario, screening limited in 1968-1978 birth cohorts could sustain treatment at levels required to achieve the HCV elimination goals. CONCLUSION: In Italy, which is an HCV endemic country, the eligible pool of patients to treat will run out between 2025 and 2028. To maintain the treatment rate and achieve the HCV elimination goals, increased case finding in targeted, high prevalence groups is required.

Dolutegravir for first-line antiretroviral therapy in low-income and middle-income countries: uncertainties and opportunities for implementation and research.

A new first-line antiretroviral therapy (ART) regimen containing dolutegravir is being rolled out in low-income and middle-income countries (LMICs). In studies from predominantly high-income settings, dolutegravir-based regimens had superior efficacy, tolerability, and durability compared with existing first-line regimens. However, several questions remain about the roll out of dolutegravir in LMICs, where most people with HIV are women of reproductive age, tuberculosis prevalence can be high, and access to viral load and HIV drug resistance testing is limited. Findings from cohort studies suggest that dolutegravir is safe when initiated in pregnancy, but more data are needed to determine the risk of adverse birth outcomes when dolutegravir-based regimens are initiated before conception. Increasing access to viral load testing to monitor the effectiveness of dolutegravir remains crucial, but the best strategy to manage patients with viraemia is unclear. Furthermore, evidence to support the effectiveness of dolutegravir when given with tuberculosis treatment is scarce, particularly in programmatic settings in LMICs. Lastly, whether nucleoside reverse transcriptase inhibitor resistance will affect the long-term efficacy of dolutegravir-based regimens in first-line, and potentially second-line, ART is unknown. Clinical trials, cohorts, and surveillance of HIV drug resistance will be necessary to answer these questions and to maximise the benefits of this new regimen.

The Continuing Burden of Advanced HIV Disease Over 10 Years of Increasing Antiretroviral Therapy Coverage in South Africa.

Background: Antiretroviral treatment (ART) has been massively scaled up to decrease human immunodeficiency virus (HIV)-related morbidity, mortality, and HIV transmission. However, despite documented increases in ART coverage, morbidity and mortality have remained substantial. This study describes trends in the numbers and characteristics of patients with very advanced HIV disease in the Western Cape, South Africa. Methods: Annual cross-sectional snapshots of CD4 distributions were described over 10 years, derived from a province-wide cohort of all HIV patients receiving CD4 cell count testing in the public sector. Patients with a first CD4 count <50 cells/µL in each year were characterized with respect to prior CD4 and viral load testing, ART access, and retention in ART care. Results: Patients attending HIV care for the first time initially constituted the largest group of those with CD4 count <50 cells/µL, dropping proportionally over the decade from 60.9% to 26.7%. By contrast, the proportion who were ART experienced increased from 14.3% to 56.7%. In patients with CD4 counts <50 cells/µL in 2016, 51.8% were ART experienced, of whom 76% could be confirmed to be off ART or had recent viremia. More than half who were ART experienced with a CD4 count <50 cells/µL in 2016 were men, compared to approximately one-third of all patients on ART in the same year. Conclusions: Ongoing HIV-associated morbidity now results largely from treatment-experienced patients not being in continuous care or not being fully virologically suppressed. Innovative interventions to retain ART patients in effective care are an essential priority for the ongoing HIV response.